Question

14. Lara bought gift cards to give as gifts. She bought some $20 movie
theater gift cards (x), and some $70 restaurant gift cards (y). Altogether,
she spent $420. This is represented by the function 20x + 70y = 420.
What is the x-intercept?

Answer 1

Answer:

21

Step-by-step explanation:

The x intercept is represented by the coordinate (x,0) on x axis.

So, to find the x intercept ,we need to equate y=0 in the equation 20x+70y=420

=> 20x+ 70*0=420

=> x=420/20 =21.

x intercept is (21,0).

Answer 2

Answer:

21

Step-by-step explanation:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

20*X+70*Y-420=0

Pull out like factors :

20x + 70y - 420  =   10 • (2x + 7y - 42)

Equation of a straight line:

y=mx+b

2x+7y-42  = 0

y-intercept = 42/7  =  6

x-intercept = 42/2  =  21